As a resident of Brooklyn, Siegel knows his city; as an author (Urban Society) and urban policy analyst, a professor of history at Cooper Union and a key figure in the 1993 election campaign of Rudolph Giuliani, he knows his cities--and the fruit of his knowledge, personal and professional, is on display in this perceptive and lively consideration of where our cities have gone, how they got there and where they might yet go. Considering New York, Washington, D.C., and Los Angeles as prime shapers of the ""national agenda,"" Siegel situates the recent (i.e., past quarter century) decline in urban life squarely on the shoulders of ""sixties liberalism."" According to Siegel it was the liberal response to the urban riots of the early to mid-1960s, particularly to the Watts riot of 1965, that set each city on its downward course, as the violence created a ""riot ideology"" that found moral and practical justification in the mayhem and, in effect, rewarded it with massive government grants, a form of ""riot insurance."" Siegel's discussion of what happened in New York focuses on the wild expansion of welfare and the attempt to decentralize schools during the period; for Washington, he concentrates on the effects of black nationalism in power, with Marion Barry at the helm; in L.A., he sees a city spinning apart from multicultural pressures. Siegel makes his points in trim prose, rooting them not in ideology but in the facts of the matter, enlivening them with telling anecdotes. This is urban analysis undertaken with a sharp, experienced eye, and with optimism as well, as Siegel finds signs of hope, particularly in Giuliani's reinvigoration of New York, that the American city has a future not only worth predicting, but worth waiting for. (Sept.)